Sulfonyl halide manufacture



Patented Nov. 6, 3951 SULFONYL HALIDE MANUFACTURE Chester E. Adams, Highland, Ind., and Wayne A. Proell, Chicago, 111., assignors to Standard Oil Company, Chicago, 111., a corporation of Indiana No Drawing. Application July 26, 1950, Serial No. 176,062

This invention relates to a novel process for the preparation of certain organic sulfonyl chlorides and bromides. More particularly, it relates to a process for the catalytic oxidation of certain organic sulfenyl chlorides and bromides with a gas containing free oxygen in the presence of nitrogen oxide catalysts,

One object of our invention is to provide a composition of said sulfenyl chlorides and bromides and in order to avoid hydrolysis of the products, viz., sulfonyl chlorides and bromides.

A further object of our inventionisto provide a two-stage process for the conversion of nontertiary hydrocarbon disulfides to the corresponding hydrocarbon sulfonyl chlorides and bromides, said process being characterized by extremely high halogen eiiiciency. These and other objects of our invention will become apparent from the ensuing description thereof.

We have discovered that certain organic sulfenyl chlorides and bromides can be smoothly oxidized to the corresponding sulfonyl compounds by oxygen in the presence of a catalytic proportion of nitrogen dioxide, or a substance yielding nitrogen dioxide under the reaction conditions, at low temperatures and pressures. The

process of the present invention is particularly applicable to non-tertiary hydrocarbon sulfenyl chlorides or bromides. The application of the catalytic oxidation process herein described and claimed makes it possible, for the first time so f far as we know, to effect the oxidation of highly unstable and novel saturated hydrocarbon sulfenyl chlorides or bromides containing at least one alpha-hydrogen atom (i. e. non-tertiary sulfenyl chlorides or bromides) to produce the corresponding sulfonyl compounds in high yields while substantially avoiding thermal decomposition of' the unstable charging stock and/or hydrolysis of the sulfonyl halide product.

Briefly, in accordance with our invention, an organic sulfenyl halide having the general formula RSX, wherein R is a non-tertiary saturated hydrocarbon radical or the like, S is sulfur 11 Claims- (Cl. 260-543) and X is a halogen selected from the group consisting of chlorine and bromine, is treated with a free oxygen-containing gas, for example, air or oxygen-enriched air, under substantially anhydrous conditions in the presence of a catalytic proportion of N01, usually varying between about 1 and about 20 percent by weight of the oxidizing gas stream, at low oxidation temperatures between about -20 C. and about 30 C., for example, about 10 C. to about 20 C., and initial partial pressures of oxygen varying from about 0.1 to about 5 atmospheres, the total pressure being ordinarily suflicient tomaintain the sulfenyl halide feed stock substantially in the liquid condition in the reaction zone. Since the catalytic oxidation process is exothermic, it is desirable to remove heat from the reaction zone at a rate suflicient to maintain the reaction temperature within desired limits.

The present oxidation process is particularly applicable to non-tertiary saturated hydrocarbon sulfenyl chlorides and bromides. Numerous aromatic sulfenyl chlorides and bromides, as well as. substituted aromatic derivatives such as m tro-derivatives thereof, have been prepared and may be employed as charging stocks. In general, aromatic sulfenyl chlorides and bromides.

are considerably more, stable, thermally, than aliphatic sulfenyl chlorides and bromides. More particularly, aromatic hydrocarbon sulfenyl chlorides and bromides are considerably more stable, thermally, than saturated hydrocarbon sulfenyl chlorides and bromides, particularly species of the latter category, which are nontertiary, i. e. which-contain hydrogen (alphahydrogen) linked to. the carbon atom which is bound to the sulfur atom of the saturated hydrocarbon sulfenyl chloride or bromide. Because of their great thermal instability, non-tertiary saturated hydrocarbon sulfenyl chlorides or bromides cannot be successfully oxidized to corresponding sulfonyl halides by theconventional techniques, employing hot concentrated nitric acid as the oxidant and glacial acetic acid as the reaction medium.

Examples'of suitable aromatic suli'enyl chloride and bromide charging stocks are those in which the aromatic radical is an aromatic hydrocarbon'radical, for example, 'phenyl, tolyl, xylyl, cumyl, ethylphenyl, naphthyl, methyl naphthyl, xenyl and the like. The aromatic radical which is linked to the sulfur in the sulfenyl chloride or bromide charging stock may also contain substituents such as halogen, nitro, carboxyl or other atoms or groups.

with air or oxygen.

Examples of saturated hydrocarbon sulfenyl I chloride and bromide charging stocks are those in which the hydrocarbon radical is non-tertiary alkyl, e. g., methyl, ethyl, n-propyl, isopropyl,

n-butyl, Z-methylpropyl, neopentyl, n-amyl, isoamyl, n-hexyl, n-octyl, isooctyl, n-decyl, n-dodecyl, n-tetradecyl, n-hexadecyl, n-octadecyl; 1 non-tertiary eycloalkyl, e. g., cyclopentyl, cyclohexyl, orthoor para-methylcyclohexyl, 2- or 3- methylcyclopentyl, bornyl; non-tertiary aralkyl, e. g., benzyl, phenethyl and the like. The saturated hydrocarbon group may be substituted by non-reactive substituents such as halogen orother groups.

The low temperature chlorinolysis of nontertiary saturated hydrocarbon disulildes to produce corresponding sulfenyl chlorides is speciflcally described and claimed in a copending application for U. S. Letters Patent, Serial No. 176,061, flled of even date herewith by Wilbur B. Chilcote and Bernard H. Shoemaker. The synthesis of tertiary alkanesulfenyl chlorides is extremely-diilicult to efiect by low temperature chlorinolysis of the corresponding disulfldes'and produces only very low yields, of the order of 5 weight percent based on disulflde feed stock.

The catalytic oxidationprocess of the present invention can be'applied to individual sulfenyl ture of alkanesulfenyl chlorides containing predominantly methyl, ethyl, n-propyl and isopropyl groups.

The sulfenyl chloride or bromide charging stock may contain non-reactive diluents, for example between about 5 and about 50 percent by volume of paraflinic hydrocarbons, small proportions of hydrocarbon disulfldes, etc. Inert dilu-.- ents or solvents may be employed in the present catalytic oxidation process but, as a rule, these are not necessary.

The catalytic oxidation process can be conducted at temperatures between about 20 C. and about C. Usually, it is convenient to operate at temperatures between about 5 C. and about 20 C. and temperatures between about 5 C. and about 10 C. are preferred, since at these temperatures the rate of oxidation of the charging stock is substantially greater than the rate of decomposition of even highly unstable charging stocks such as methanesulfenyl chloride, ethanesulfenyl chloride and the like. However, it will be apparent that when more stable charging stocks are employed, for example, phenylsulfenyl chloride or o-nitrophenylsulfenyl chloride, higher reaction temperatures between about 20 C. and about 40 C. can be conveniently employed, and in general the reaction temperature'is adjusted to the stability of the sulfenyl halide.

The oxidant in the present process is oxygen, which may be employed as such. However, it is preferable to employ relatively dilute oxygen streams, for example as in air, flue gases containing desired proportions of oxygen, mixtures 1 of oxygen with C02 or gaseous hydrocarbons such as methane or ethane, and the like.

The initial partial pressure of oxygen charged to the oxidation reaction zone may be varied between about 0.1 and about 5 atmospheres and is usually selected between about 0.2- and 0.5 atmosphere. It will be apparent that the oxidation rate will increase with increasing oxygen partial pressures in the reaction zone under otherwise constant reaction conditions, particularly catalyst concentration. The total pressure in the oxidation reaction will usually vary between about 15 and about p. s. l. g. As will be apparent from the operating examples hereinafter set forth, the catalytic oxidation process can be conveniently effected at substantially atmospheric pressure, employing air as the oxidant gas stream.

The essential catalyst employed in the present process is nitrogen dioxide. Ordinarily, nitrogen dioxide concentrations between about; 0.05 and about 1 part by weight of N02, per part by weight of oxygen can be employed. The rate of oxidation tends to increase with increasing .N02 concentration in the reaction zone, other reaction conditions remaining constant. As will appear hereinafter in certain operating examples, the induction period frequently encountered in the oxidation process can be appreciably reduced by initiating reaction in the presence of relatively large proportions of N02, for example between about 0.5 and about 5 parts by weight of N02 per part by weight of oxygen, following which the N02 concentration in the oxidant gas stream can be reduced to a substantially lower level, for example between about 0.01 and about 1 part by weight of N02 per part by weight of oxygen, and the reaction can then be continued to the desired extent or to completion.

It will be apparent that in lieu of or in addition to N02, we can employ materials which will yield N02 in the oxidation reaction zone under the reaction conditions. Thus, for example, as

is well-known, N0: is ordinarily in equilibrium apparent, therefore, that in lieu of or in addition to N02, we may employ N0, N203, N204 and N205. Although it is well-known that nitric acid can decompose under certain conditions to yield N02, ordinarily we do not desire to employ nitric acid as a source of catalyst, since its decomposition also yields water, and it is desired to effect the present process in the substantial absence of water, which leads to undesirable side reactions such as hydrolysis of the charging stock and I minutes.

as nitrosylsulfonic acid, can be distilled out or stripped therefrom by a stream of stripping gas I such as nitrogen, air, CO: or the like, and thereafter recovered by conventional methods and reused. Catalyst present in the eiiluent gas stream during the operation of the present processcan, likewise, be recovered by conventional means and recycled for use in the present process.

The reaction period will depend, to a considerable extent, upon the extent of oxidation sought to be eifected and upon the other reaction conditions such as temperature, oxygen concentration, catalyst concentration, reactivity of the particular charging stock, intimacy of contact, etc. Ordinarily, substantial oxidation can be effected within reaction periods selected with the range of about 60 to about 600 minutes. It will be apparent that desirable reaction periods can readily be determined by small scale runs in batchwise, continuously or semi-continuously.

The oxidation process may also be effected in a number of stages, with or without product separation between stages. The oxidation reaction may be eflected in conventional reaction kettles or autoclaves, or in a tubular converter or contacting tower. A suitable form of reactor is a vertical tower provided with contacting means such as bubble cap trays or with packing such 'as ceramic bodies or fiber glass mats. Concurrent contacting of liquid sulfur compound feed stock and the oxidizing gas stream proceeds efficiently in the types of reaction tower just described; the liquid feed is passed downwardly through the tower together with a stream of oxidizing gas, all of which may be admitted at a point near the top of the tower or in. aliquot portions at vertically spaced points along the tower. A tubular reactor equipped for spacedjinjection of oxidizing gas into a flowing stream of liquid or vaporized feed stock and oxidation products may also be employed; a reactor of this type permits fine control of the extent of oxidation.

- The following operating examples are included for the purpose of illustrating specific appliestionsof the invention and not with the intent of unnecessarily delimiting the same.

EXAMPLE 1 (51.3 g.) was contacted with mixture of 16 weight percent NO: and 84 percent dry air was passed therethrough at the rate of 1 was considered completed at the end of 284 T at which time very little further amounts, of oxygen were being absorbed by the 6 a of ethanesulfonyi chloride, boiling range 175- 181' C., a 1.4820. The ethanesulfonyl chloride was separated from the reaction products by distillation under a pressure of 2mm. of mercury. The yield of ethanesulfonyl chloride was 05.5 percent of theoretical, based on the amount of ethanesulfenyl chloride available for the oxida- 1 tion reaction. The bottoms obtained by vacuum distillation of the reaction mixture contained 8.79 g. of acid. calculated as ethanesulfonic acid.

1 EXAMPLE 2 chlorinolysis of ethyl disulfide (25 g.) was effected by the absorption of 14.5 g. of chlorine therein at'temperatures between 23 and 32C. over the course of minutes. The crude reaction mixture was stripped with dry nitrogen to 'ilush unreacted chlorine therefrom. The crude reaction mixture was then contacted with 'a' gas stream containing between 13 and 20 weight percent N02, the remainder being dry air at the rate 'of 0.8 cubic foot per hour (standard conditions). A smooth oxidation reaction ensued at room temperature- (21-29 C.) and was completed in 240 minutes. The oxidation reaction products were fractionally distilled under a pressure of 1.4 mm. of mercury, yielding 29.7 g. of ethanesulfonyl chloride, boiling range 177-185 C., a 1.4820,

which is equivalent to 56.5 percentcf thecry based on the disulfide charging stock.

' EXAMPLE 3 foot per hour at 20 mm. of mercury pressure.

This was followed by a 15 minute flush with dry nitrogen to remove unreacted chlorine. Samples were then withdrawn and the z-butanesulfenyl chloride content found to be 89 percent by K1 titration. The chlorinolysis reaction mixture was then treated in the same reactor with a mixture of 15 weight percent N0: and 85 weight percent dryair at temperatures between 11 and 25C. at the rate of 0.9 cubic foot per hour (standard conditions) Oxidation began immediately and proceeded smoothly, accelerating to maximum absorption of percent oxygen at 80 minutes. Oxidation was complete in 244 minutes. Distil-' lation at 1.0 mm. mercury pressure yielded 56.2 g. (.359 mols) of 2-butanesulfonyl chloride boiling at 204-205 C. at 1 atmosphere (38 C. at 1.0 mm., 44 C. at 1.70 mm. of mercury), n 1.4527, containing 20.2 percent sulfur and 22.6 percent chlorine. The yield was 88 percent of theory based on .2-butanesulfenyl chloride available for reaction and 78 percent based on the disulflde charging stock. The bottoms had an acidity equivalent to 3.49 g. (0.0253 'mols) of the corresponding sulfonic acid.

EXAMPLE4 Plant disulflde oil having an average molecu-,

lar weight of 122 (58.2 g.; 0.475 mol calculated as ethyl disulfide) was charged to the glass reactor employed in Example 3. .Chlorinolysis' was effected for 1'75 minutes with a mixture of chlo-. rine and dry nitrogen at such a rate that .209 gram (.00294 mol), of chlorine per minute entered the reactor. The temperature was maintained in 7 V the range of 30 to -40 C. A 15 minute flush with dry nitrogen served to carry out any unreacted chlorine. Samples were withdrawn and the R801 content found to be '74 percent, calcu-v lated as ethanesulfenyl chloride, by K1 titration. 5 The crude mixed sulfenyl chlorides were then treated in the same reactor at 17 to 23 C. witha mixture of 23 percent NO: and 77 percent air for 158 minutes (at the rate of .75 cubic feet of air .employed as starting materials to effect numerous chemical conversions. The non-tertiary alkanesulfonyl chlorides produced by the present process can -be hydrolyzed to produce pure al- ,kanesulfonic acids which can be employed as electroplating media, especially for high speed (high current density). copper plating baths.

1 40% initial; than 8%.

per hour, standard conditions). Oxidation bein The pure sulfonic acids are also highly useful gan immediately and accelerated to a peak oxyesterifloation catalysts, especially for the esterigen absorption rate of 100 percent at 103 minutes. flcation of acid-sensitive materials such as cellu- When oxidation ceased, the products were re lose, glycols, polybasic acids, etc. v moved from the reactor, benzene (as a solvent) Copending Serial No. 176,063 of even date, flled serving to eifect good transfer, washed with 50 cc. by Wayne A. Proell and Wilbur B. Chilcote reof water and then distilled. Mixed sulfonyl latcs to the use of partially oxidized feedstock chlorides (80.9 8-) Were obtained and found to as a primer to avoid an induction period inIN Ozhave the following inspections: catalyzed oxidation of sulfonyl halides. Copend inggerial 1:0. 176,064 of even date, filed by Wayne 4 n 1 A. cell c al. relates to a one-step process for Win Ram Page t Pal-(gent "P the preparation of sulfonyl chlorides by the treatment of hydrocarbon disulfldes with chlorine and 12.1- as c. at 19 mm. to 45 0. 14. 2 26.68 1. 4551 oxygen in the presence of NO: catalyst. 2E 31? mmtow C 2254 m 12 U568 lfiiglviigg thus described our invention, what we at 3.5 mm. o I c a 2, if mm 1. A processfor the preparation of-a hydro- 13.0---- 44t(%.gt3.8mm.t045 0. 22-64 M 8 carbon sulfonyl halide having the general for- 20.0...- e ciaifthmwe 0. am 25.50 1.4588 m Rsoex wherein R is a n i ry hydroat m carbon radical and X is selected from the class consisting of chlorine and bromine, which proc- The boiling range of the products indicates the 6 comprises contacting the corresponding hy presence of methane, ethane and isomeric prodrocarbon sulfenyl halide in an oxidation zone panesulfonyl chlorides. The yield, assuming the with a v gas containing free oxy en and a'catamixed sulfonyl chlorides to have the average lytic quantity, of nitrogen dioxide at a reaction molecular weight of ethanesulfonyl chloride. was temperature between about C- m! ab ut 66.6 percent based on disulfide oil charged and 90 C- W i e Su tially x ludin Water from percent based on the sulfenyl chloride content said oxidation zone. a of the disulfide oil which had-been subjected to 2. A process for the preparation of a non-terlow temperature chlorinolysis. tlary saturated hydrocarbon sulfonyl chloride,

Data from the above and two additional exwhich process comprises contacting the correamples are presented in the following table. sponding non-tertiary saturated hydrocarbon In general, it may be said that the reaction sulfenyl chloride in an oxidation zone with a'gas pr du ts a han n nta c ncontaining free oxygen and a catalytic quantitysiderable di ve N 2. and n sr lf of nitrogen dioxide at a reaction temperature beacids, inaddition to the sulfonyl chlorides and 45. about .-..g Q and about 0 Q m sulmnic anhydridefi The? cmwen' stantially excluding water from said oxidation iently worked up by direct distillation, dilrin which 201m case provision must be made for han g the mm m or by mm and ;?.f.i 2%tt ;if3325; distilling. The latter procedure removes all ni- Rsoel g m g 'trogen oxides and sulfonic acids, leaving a crude w ere is non'ter-tiary alkyl sulfonyl chloride of fairly good purity. This 3 Pmcess mprises the latter material is distilled, which removes water responding hydrocarbon u chloride in an and yields a pure sulfonyl chloride as distillate. oxidation with a wntammg free oxygen sulfonyl chlorides hydrolyze at room temperature and catalytlc quantlty nitmgen m i at at a slow rate and it is advisable not to allow wet a reaction peratu e etwee about 0 and sulfonyl chlorides, to stand too long. The disabout 30C. while substantially excluding water tilled sulfonyl chlorides are usually water-white from said oxidation zone. mobile oils, identifiable by refractive index and 4. The process of claim 3 wherein the sulfenyl by characteristic sulfonamide derivatives. chloride is ethanesulfenyl chloride.

Table Time, Min. Temp., 0. gmsgg R30 01 A NOIIW" Yield Yiel d. BSCl Based on 2. &1? Chlorination 1%,? o as nsoioi asoion B801 Ethyl Disulilde--- 145- 284 -zom-ao 141.025 is can as 9.5 04.1 do 240 am 32 21am 13 we so z-Butyl Disu1iide as 244 -30to40 llto25 15 as 11 4 as Plant Dlsulfldes... 15s -3om -4o 11cm 23 14.1 we 00 Ethyl Disulflde--- no 20m -ao l6to28 4o s1 12 on m 286 +14m+21 llto2l 24 91 12.0 12.85 80.7

5. The process of claim 3 wherein the sulfenyl chloride is z-butanesulfenyl chloride.

6. The process of claim 3 wherein the sulfenyl chloride is a mixture of alkanesulfenyl chlorides containing 1 to 3 carbon atoms, inclusive, in the alkyl group.

7. A unitary process for the production of a non-tertiary saturated hydrocarbon sultonyl chloride, which process comprises contacting a non-tertiary saturated hydrocarbon disulflde with chlorine at a chlorinolysis reaction temperature between about 40 C. and about 20 C., employing sufficient chlorine to ei'lect substantial chlorinolysis of said disuliide but insuflicient to eflect quantitative chlorinolysis in order to produce a chlorinolysis reaction mixture containing at least 5 percent of unconverted hydrocarbon disulflde, initiating oxidation by subjecting the resultant crude chlorinolysis reaction mixture without purification to contact in an oxidation reaction zone with an oxidant gas containing free oxygen and also nitrogen dioxide in an amount between about 0.5 and about 5 parts by weight per part by weight of the oxygen present in said oxygen-containing gas at a temperature between about 20 C. and about 30 C. while substantially excluding water -i'rom said oxidation reaction zone and, after the onset of substantial oxidation, reducing the proportion of NO: to a value between about 0.05 and about 0.5 part by weight per part by weight of oxygen in said oxidant gas and continuing the oxidation.

8. A process for the preparation of a hydrocarbon sulfonyl halide having the general formula RSOzX wherein R is a non-tertiary hydrocarbon radical and X is selected from the class consisting of chlorine and bromine, which process comprises contacting the corresponding hydrocarbon sulIenyl halide in an oxidation zone with a gas containing free oxygen and a catalytic quantity oi nitrogen dioxide at a reaction temperature between about 5 C. and about 20 C. while substantially excluding water from said oxidation zone.

9. A process for the preparation of a non-tertiary saturated hydrocarbon sulfonyl chloride, which process comprises contacting the corresponding non-tertiary saturated hydrocarbon sultenyl chloride in an oxidation zone with a gas containing free oxygen and a catalytic quantity of nitrogen dioxide at a reaction temperature between about 5 C. and about 20 C. while substantially excluding water from said oxidation zone.

10. A unitary process for the production of a non-tertiary saturated hydrocarbon sulfonyl chloride, which process comprises contacting a non-tertiary saturated hydrocarbon disuliide with chlorine at a chlorinolysis reaction temperature between about -40 C. and about 20 C. to produce a reaction mixture containing a substantial proportion of a non-tertiary saturated hydrocarbon sulfenyl chloride, thereafter contacting said reaction mixture in an oxidation zone with a gas containing free oxygen and a catalytic quantity of nitrogen dioxide at a reaction temperature between about 20 C. and about 30 C. while substantially excluding water from said oxidation zone, and separating a nontertiary saturated hydrocarbon sulfonyl chloride so produced.

11. The process of claim 10 wherein the reaction temperature in said oxidation zone is between about 5 C. and about 20 C.

Oil-ESTER E; ADAMS. WAYNE A. PROELL.

No references cited. 

7. A UNITARY PROCESS FOR THE PRODUCTION OF A NON-TERTIARY SATURATED HYDROCARBON SULFONYL CHLORIDE, WHICH PROCESS COMPRISES CONTACTING A NON-TERTIARY SATURATED HYDROCARBON DISULFIDE WITH CHLORINE AT A CHLORINOLYSIS REACTION TEMPERATURE BETWEEN ABOUT -40* C. AND ABOUT 20* C., EMPLOYING SUFFICIENT CHLORIDE TO EFFECT SUBSTANTIAL CHLORINOLYSIS OF SAID DISULFIDE BUT INSUFFICIENT TO EFFECT QUANTITATIVE CHLORINOLYSIS IN ORDER TO PRODUCE A CHLORINOLYSIS REACTION MIXTURE CONTAINING AT LEAST 5 PERCENT OF UNCONVERTED HYDROCARBON DISULFIDE, INITIATING OXIDATION BY SUBJECTING THE RESULTANT CRUDE CHLORINOLYSIS REACTION MIXTURE WITHOUT PURIFICATION TO CONTACT IN AN OXIDATION REACTION ZONE WITH AN OXIDANT GAS CONTAINING FREE OXYGEN AND ALSO NITROGEN DIOXIDE IN AN AMOUNT BETWEEN ABOUT 0.5 AND ABOUT 5 PARTS BY WEIGHT PER PART BY WEIGHT OF OXYGEN PRESENT IN SAID OXYGEN-CONTAINING GAS AT A TEMPERATURE BETWEEN ABOUT -20* C. AND ABOUT 30* C. WHILE SUBSTANTIALLY EXCLUDING WATER FROM SAID OXIDATION REACTION ZONE AND, AFTER THE ONSET OF SUBSTANTIAL OXIDATION, REDUCING THE PROPORTION OF NO2 TO A VALUE BETWEEN ABOUT 0.05 AND ABOUT 0.5 PART BY WEIGHT PER PART BY WEIGHT OF OXYGEN IN SAID OXIDANT GAS AND CONTINUING THE OXIDATION. 